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Verne Charles Fryklund

Publications and source records attributed to Verne Charles Fryklund.

5 recordsLinked to original sources
USGS1963

The abundance of scandium in volcanic rocks, a preliminary estimate

Using Rittman's classification to determine the clan, we suggest the following abundance figures: basalts (99), 38 p.p.m. Sc; andesites (72), 34 p.p.m. Sc; dacites (68), 21 p.p.m. Sc; rhyodacites (32), 14 p.p.m. Sc; quartz latites (14), 11 p.p.m; rhyolites (24), 5 p.p.m. The scandium was determined spectrographically on samples for which there were complete rock analyses. In addition we suggest that extrusive equivalents of peridotites should contain about 9 p.p.m. Sc; extrusive equivalents of perknites should contain about 30 p.p.m. Sc. We see no reason why these figures should not apply to the intrusive equivalents. We tentatively suggest a figure of 30 p.p.m. for Sc for the crust, using Poldervaart's suggested ratio of rock types.

Geochimica et Cosmochimica Acta↗
USGS1962

Temperature of crystallization of pyrrhotite and sphalerite from the Highland-Surprise Mine, Coeur d'Alene district, Idaho

The ore bodies of the Highland-Surprise Mine are replacements along shear zones in quartzose slate, quartzite, and phyllite of the Prichard Formation of the Belt series (Precambrian). Pyrite, arsenopyrite, pyrrhotite, sphalerite, chalcopyrite, and galena are the chief metallic minerals and were probably deposited in that order. Temperatures of formation were estimated for pyrrhotite-pyrite and sphalerite-pyrrhotite assemblages contained in the steeply dipping vein system. Measurements on 62 pyrrhotites indicate a range in temperature of crystallization between 370 degrees and 492 degrees C. (no correction required for confining pressures <2000 bars below 670 degrees C.), and measurements on 14 sphalerites indicate crystallization temperatures between 375 degrees and 460 degrees C. (uncorrected for confining pressure). No systematic temperature gradients were recognized. Minor elements in 23 pyrrhotite, 8 pyrite, 13 sphalerite, and 2 galena samples were determined. Partition ratios of Ni and Co in pyrrhotite-pyrite and sphalerite-pyrrhotite pairs are erratic. This suggests a dis-equilibrium distribution of these elements between the phases of each mineral pair and/or b) crystallization of the mineral pairs under different physical conditions.

Idaho↗
USGS1954

The occurrence of cobalt and nickel in the Silver Summit Mine, Coeur d'Alene district, Idaho

Cobalt and nickel of possible commercial interest have been discovered in the Silver Summit mine, Coeur d'Alene district, Idaho. Assay data indicate that an ore shoot contained about 0.40 percent cobalt and about 1.0 percent nickel in addition to the copper and rich silver ores. The cobalt-nickel mineral gersdorffite occurs in tetrahedrite-siderite veins. Gersdorffite is widespread in small amounts and appears to have been the first of the "ore shoot" minerals. The known occurrence of either cobalt bloom or gersdorffite in other properties of the Coeur d'Alene district Silver Belt suggests that other ore shoots may exist that contain commercial quantities of cobalt and nickel.

Idaho↗
USGS1953

Niobium (columbium) and titanium at Magnet Cove and Potash Sulphur Springs, Arkansas

This work was done because niobium (columbium) has been found in several of the minerals and rocks of the Magnet Cove and Potash Sulphur Springs areas. Niobium is in demand for use in high-temperature and non-creep steels. The Magnet Cove and Potash Sulphur Springs areas are in central Arkansas between Malvern and Hot Springs. They are underlain by similar alkaline igneous complexes consisting of nepheline syenite, more basic alkaline rocks, and calcite rock or carbonatite. The igneous rocks intrude Paleozoic sedimentary rocks and are truncated by a Late Cretaceous erosion surface. At Magnet Cove deposits of rutile (TiO 2) occur within the igneous complex; two deposits of brookite (TiO 2 ) occur in quartzite of the Arkansas novaculite formation of probable Devonian and Mississippian age, near the margin of the complex. Perovskite (calcium titanate) occurs in several places in the igneous complex. Niobium is present in rutile, brookite, and perovskite, and also probably in other minerals not yet analyzed. In order to determine the distribution and average content of niobium in the larger titanium deposits, drill core and channel samples were analyzed for niobium, titanium, and other elements; and average figures were calculated. Concentrates and single crystals were also analyzed. Material from drill cores of perovskite-bearing magnetite-pyroxene rock on the Mo-Ti Corporation property was studied and analyzed. The Kimsey calcite quarry area was mapped, and channel samples and single crystals were analyzed. Channel samples from trenches on the Wilson prospect at Potash Sulphur Springs were analyzed. The areas studied contain large resources of titanium and niobium, of low grade. The major results of the analytical work are summarized in the following table.

Arkansas↗